Pedro Becker

The empty sella: results of treatment in 76 successive cases and high frequency of endocrine and neurological disturbances

OBJECTIVE We assessed the frequency of endocrine or neurological disturbances and the results of surgery in patients with empty sella, diagnosed with cisternography and/or computerized tomography scanning.

Renal function and cardiopulmonary bypass in pediatric cardiac surgical patients.

We studied prospectively the perioperative changes of renal function in nine children undergoing cardiac surgery with cardiopulmonary bypass (CPB). Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were measured with inulin and 131I-hippuran clearances before CPB, during hypo and normothermic CPB, following sternal closure and 1 h postoperatively. Urinary alpha glutathione S-transferase (alpha GS-T) was measured pre- and postoperatively as a marker for tubular cellular damage. Plasma and urine creatinine and electrolytes were measured. Free water, osmolal and creatinine clearances, as well as fractional excretion of sodium (FeNa) and potassium transtubular gradient (TTKG) were calculated. GFR was normal before and after surgery. ERPF was low before and after surgery; it increased significantly immediately after CPB. Filtration fraction (FF) was abnormally elevated before and after surgery; however, a significant decrease during normothermic CPB and sternal closure was found. Alpha GS-T presented a moderate, but nonsignificant increase postoperatively. FeNa also increased in this period, but not significantly. Creatinine, osmolal, free water clearances, as well as TTKG, were normal in all patients pre- and postoperatively. We conclude that there is no evidence of clinically significant deterioration of renal function in children undergoing repair of cardiac lesions under CPB. Minor increases of alpha GS-T in urine postoperatively did not confirm cellular tubular damage. There was no tubular dysfunction at that time.

Survival of Newborn Infants With Severe Respiratory Failure Before and After Establishing an Extracorporeal Membrane Oxygenation Program

Background: Severe hypoxic respiratory failure is a leading cause of neonatal mortality in Chile. Extracorporeal membrane oxygenation improves survival in neonates with hypoxic respiratory failure. Objective: To determine the impact of the establishment of a Neonatal Extracorporeal Membrane Oxygenation Program on the outcome of newborns with severe hypoxic respiratory failure in a developing country. Design/Patients: Data of newborns (birthweight > 2,000 g and gestational age ≥ 35 wk) with hypoxic respiratory failure and oxygenation index greater than 25 were compared before and after extracorporeal membrane oxygenation was available. Extracorporeal membrane oxygenation was initiated in infants with refractory hypoxic respiratory failure who failed to respond to inhaled nitric oxide/high-frequency oscillatory ventilation. Main Results: Data from 259 infants were analyzed; 100 born in the pre-extracorporeal membrane oxygenation period and 159 born after the extracorporeal membrane oxygenation program was established. Patients were similar in terms of risk factors for death for both periods except for a higher oxygenation index and a greater proportion of outborn infants during the extracorporeal membrane oxygenation period. Survival significantly increased from 72% before extracorporeal membrane oxygenation to 89% during the extracorporeal membrane oxygenation period (p < 0.01). During the extracorporeal membrane oxygenation period, 98 of 159 patients (62%) with hypoxic respiratory failure were rescued using inhaled nitric oxide/high-frequency oscillatory ventilation, whereas 61 (38%) did not improve; 52 of these 61 neonates were placed on extracorporeal membrane oxygenation. Extracorporeal membrane oxygenation survival rate to discharge was 85%. After adjusting for potential confounders, the severity of the pretreatment oxygenation index, a late arrival to the referral center, the presence of a pneumothorax, and the diagnosis of a diaphragmatic hernia were significantly associated with the need for extracorporeal membrane oxygenation or death. Conclusions: The establishment of an extracorporeal membrane oxygenation program was associated with a significant increase in the survival of newborns more than or equal to 35 weeks old with severe hypoxic respiratory failure.

Persistencia del estrés oxidativo postrasplante cardíaco: estudio comparativo entre pacientes con trasplante cardíaco y con insuficiencia cardíaca crónica estable

Introduccion y objetivo Existe estres oxidativo en pacientes con insuficiencia cardiaca cronica (ICC). El trasplante cardiaco, alternativa terapeutica importante en estos pacientes, podria disminuir el estres oxidativo al mejorar la funcion cardiaca. Nuestro objetivo fue evaluar el estres oxidativo postrasplante cardiaco. Pacientes y metodo Fueron estudiados 3 grupos experimentales: a) trasplantados cardiacos, sin evidencia de rechazo (n = 11); b) pacientes con ICC capacidad funcional III de la NYHA (n = 19), y c) sujetos controles sanos (n = 14). El estres oxidativo se evaluo determinando valores plasmaticos de malondialdehido (MDA), y actividades de glutation peroxidasa (GSH-Px), catalasa (CAT) y superoxido dismutasa (SOD). Resultados Las caracteristicas demograficas fueron similares entre los grupos. El tiempo postrasplante fue 20,0 ± 4,8 meses. Los valores de MDA en trasplantados y con ICC fueron significativamente mayores que en sujetos normales (3,35 ± 0,8; 3,27 ± 1,7, y 0,90 ± 0,3 µM, respectivamente). La actividad de GSH-Px aumento en trasplantados respecto al grupo control (0,40 ± 0,07 y 0,33 ± 0,05 U/g Hb, respectivamente). La actividad de SOD fue menor en trasplantados respecto al grupo control ICC (0,44 ± 0,1 frente a 0,87 ± 0,6 U/mg Hb). No hubo diferencias en las actividades de CAT entre trasplantados y pacientes con ICC. Conclusion Los pacientes sometidos a trasplante cardiaco tienen un aumento del estres oxidativo, evidenciado por una elevacion del MDA y por una disminucion de la actividad de SOD, a pesar de una mayor actividad de GSH-Px. Este aumento del estres oxidativo fue similar al encontrado en pacientes con ICC estable CF III de la NYHA, y se observo en ausencia de episodios reconocidos de infeccion o rechazo.

New Surgical Approach to Device Closure of Multiple Apical Ventricular Septal Defects

We present an alternative technique for closing multiple ventricular septal defects difficult to access during surgery. A guidewire is advanced through the right ventricular free wall and through the main apical defect to the left ventricle, and this approach is used to place an Amplatzer device to occlude the ventricular septal defects. The procedure is performed in the beating heart, under intraoperative transesophageal echocardiographic guidance, and without extracorporeal circulation. It appears to be a simple and reproducible procedure with excellent short-term results.

Cierre perventricular de la comunicación interventricular múltiple con dispositivo Amplatzer

Se presenta una tecnica alternativa para el cierre de la comunicacion interventricular de dificil acceso quirurgico. Con el corazon latiendo y sin necesidad de circulacion extracorporea, se punciona el ventriculo derecho y se avanza una guia de alambre hasta el ventriculo izquierdo a traves del defecto apical principal; esto permite colocar un dispositivo Amplatzer que ocluye completamente los defectos. El procedimiento se realiza con vision ecocardiografica transesofagica, es simple y con excelentes resultados a corto plazo.

Revascularización miocárdica de la arteria descendente anterior con anastomosis mamaria con técnica clásica

Introduccion y objetivos Establecer los resultados obtenidos con la tecnica clasica de anastomosis de la arteria descendente anterior. Material y metodos Entre enero de 1982 y julio de 1997, 154 pacientes fueron sometidos a cirugia de revascularizacion de la arteria descendente anterior con mamaria usando tecnica clasica (esternotomia y circulacion extracorporea). Resultados En nuestro grupo no hubo mortalidad, infarto perioperatorio ni accidente vascular encefalico. Un paciente (0,6%) tuvo infeccion de la herida esternal y otro (0,6%) presento sangrado postoperatorio que requirio reoperacion. Se obtuvo un 100% de seguimiento entre 3 y 183 meses (promedio, 64,4 meses). La supervivencia actuarial global a los 5, 10 y 15 anos fue del 95,6 ± 2,1%; 92,1 ± 4% y 85,5 ± 7,5%, respectivamente, y la probabilidad actuarial de estar libre de muerte cardiaca fue de 99 ± 0,9%; 99% y 99%. La probabilidad actuarial de estar libre de infarto a los 5, 10 y 15 anos fue de 99 ± 0,9%, 99% ± 0,9% y 99%, y la de estar libre de angina del 95 ± 2,2%; 86,9 ± 4,9% y 74,5 ± 12,2%. Finalmente, la probabilidad actuarial de estar libre de reoperacion y de angioplastia a los 5, 10 y 15 anos fue del 99 ± 0,9%, 99%, 99% y 96,9 ± 1,7%, 91,4 ± 4.1% y 91,4 ± 4,1%, respectivamente. La cuenta hospitalaria promedio en el ultimo 10% de este grupo fue 199,8 UF (6.200 dolares). Conclusion La revascularizacion miocardica a la descendente anterior con arteria mamaria unica, con tecnica clasica, es un procedimiento seguro, de minimo riesgo, de bajo coste y de excelentes resultados a los 10 y 15 anos

Mortalidad operatoria y estratificación de riesgo en pacientes pediátricos operados de cardiopatía congénita: experiencia de 10 años

Estudio de cohorte no concurrente (ene-ro 2000-julio 2010). Las cirugias fueron estratificadas segun puntuacion de riesgo. La tendencia de morta-lidad operatoria se evaluo dividiendo el periodo es-tudiado en tres subperiodos. Comparamos nuestros resultados con los publicados por las Sociedades de Cirujanos de Cardiopatias Congenitas y la de Ciruja-nos de Torax.

Morbimortalidad precoz y alejada del reemplazo valvular aórtico con prótesis mecánica y biológica durante la última década: El estándar de oro

BACKGROUND There is a growing interest in alternative techniques for aortic valve replacement (AVR). Therefore it is important to have updated results of conventional AYR as a valid comparative standard. AIM To evaluate both perioperative and late morbidity and mortality in patients undergoing conventional AVR, with either mechanical (RVAm) or biological (RVAb) prostheses. PATIENTS AND METHODS Retrospective review of medical records and operative protocols of patients undergoing AVR between January 1995 and December 2005. Patients with previous cardiac surgery, aortic balloonplasty or simultaneous cardiovascular procedures were excluded. RESULTS During the study period, 788 patients underwent AVR and 317 met the inclusion criteria. Of the latter, 175 patients aged 13 to 83 years (63% males) were subjected to AVRm and 142 patients aged 49 to 87 years (64% males), were subjected to AVRb. Five (1.6%) patients died during the perioperative period (one AVRm and four AVRb). All were older than 65 years. Perioperative complications were recorded in 29 and 25% of patients in AVRm and AVRb groups, respectively (NS). During a median follow-up of six years, complications were recorded in 12 and 4% of patients in AVRm and AVRb groups, respectively (p <0.05). The actuarial survival for AVRm group at 1, 5 and 10 years, was 96, 92 and 87%, respectively. The figures for AVRb group were 95, 86 and 83%, respectively (NS). The 10 year reintervention free survival was 97% for the AVRm group and 84% for the AVRb (p <0.05). CONCLUSIONS Perioperative mortality and rates of complications of AVR in this series of patients are low, which compares favorably with other series.

Cirugía coronaria en el infarto de miocardio de menos de 24 horas de evolución

Background. Thrombolysis and angioplasty in the first hours after myocardial infarction minimize necrosis, leading to better early and late survival, but these therapies have limited effect in patients with three-vessel disease and cardiogenic shock. Emergency coronary surgery is an alternative treatment in some cases. Aim. To assess perioperative complications, mortality and long-term survival in patients undergoing coronary surgery within 24 h of myocardial infarction. Patients and methods. We retrospectively studied 57 patients undergoing surgery within 24 h of the onset of symptoms of myocardial infarction between 1982 and 1998. Multiple vessel disease was present in 31 patients (54%), shock or cardiac arrest in 19 (33%) and coronary angiography complications in 7 (12%). The mean time between onset of symptoms and surgery was 6.32 h. At the beginning of surgery 32 patients (56%) were hemodynamically stable, 15 (26%) were in shock and 10 (17%) were in cardiac arrest. Results. The operative mortality was 0% for those who were hemodynamically stable at the start of surgery and 44% (11 of 25 patients) for those in shock or cardiac arrest. Shock or prior cardiac arrest were associated with higher rates of sternal infection and heart failure and longer hospital stays. Follow-up (mean 67 months) was possible for all remaining patients. The 5- and 10-year survival rates were 89 and 82%, respectively, for patients who were hemodynamically stable at the time of surgery. Five-year survival was 55%, however, for those who underwent surgery in shock or cardiac arrest. The overall rate of freedom from myocardial infarction, angioplasty or reoperation was over 95% at 5 years and over 85% at 10 years of follow-up. Age and shock or cardiac arrest were risk factors for a poor long-term outcome. Conclusion. The early and long-term outcome of coronary surgery within 24 h of myocardial infarction is good for patients who are hemodynamically stable when surgery begins. Shock and cardiac arrest are important risk factors for complication and death. Coronary artery bypass grafting is a good treatment option in the first hours after myocardial infarction.